The present disclosure relates generally to medical prosthesis deployment systems for vascular repair. More particularly, the present disclosure relates to a deployment system for a prosthesis to repair a transected body vessel for gaining hemostasis during emergency medical procedures.
Trauma physicians frequently encounter patients having traumatic injury to a body vessel, such as lacerated vessels or even transected vessels, resulting from gunshots, knife wounds, motor vehicle accidents, explosions, etc. Significant damage to a body vessel may expose a patient to deleterious conditions such as the loss of a limb, loss of function of a limb, increased risk of stroke, impairment of neurological functions, and compartment syndrome, among others. Particularly severe cases of vascular injury and blood loss may even result in death. In such severe situations, the immediate goal is to obtain hemostasis while maintaining perfusion of adequate blood flow to critical organs, such as the brain, liver, kidneys, and heart.
Examples of treatment that are commonly performed by trauma physicians to treat body vessel injuries include clamping the vessel with a hemostat, use of a balloon tamponade, ligation of the damaged vessel at or near the site of injury, or the insertion of one or more temporary shunts. However, conventional surgical repair is generally difficult with such actively bleeding, moribund patients. In many instances, there is simply not enough time to repair the body vessel adequately by re-approximating and suturing the body vessel. In many situations, the trauma physician will simply insert a temporary shunt (such as a Pruitt-Inahara Shunt) into the vessel. However, use of temporary shunts has been linked to the formation of clots. This may require returning the patient to the operating room for treatment and removal of the clots, often within about 36 to 48 hours of the original repair. Since shunts are generally placed as a temporary measure to restore blood flow and stop excessive blood loss, the shunt is typically removed when the patient has stabilized (generally a few days later) by a specialized vascular surgeon. After removal, the vascular surgeon will replace the shunt with a vascular graft, such as a fabric graft that is sewn into place. Ligation of the damaged blood vessel may result in muscle necrosis, loss of muscle function, or a potential limb loss or death.
Due to the nature of the body vessel injury that may be encountered, the use of shunts, repairing and/or ligating of a blood vessel often requires that such treatments be rapidly performed at great speed, and with a high degree of physician skill. Such treatments may occupy an undue amount of time and attention of the trauma physician at a time when other pressing issues regarding the patient's treatment require immediate attention. In addition, since the level of particularized skill required may exceed that possessed by the typical trauma physician, particularly traumatic episodes may require the skills of a physician specially trained to address the particular trauma, such as a vascular trauma, and to stabilize the patient in the best manner possible under the circumstances of the case.
Some open surgical techniques utilize sutures to affix damaged tissue portions surrounding fittings that have been deployed with the vessel, which requires the trauma physician to take time to tie the sutures properly. Although in modern medicine sutures can be tied in relatively rapid fashion, any step in a repair process that occupies physician time in an emergency situation is potentially problematic. In addition, the use of sutures to affix the vessel to the fitting compresses the tissue of the vessel against the fitting. Compression of tissue may increase the risk of necrosis of the portion of the vessel tissue on the side of the suture remote from the blood supply. When present, necrosis of this portion of the vessel tissue may result in the tissue separating at the point of the sutures. In this event, the connection between the vessel and the fitting may eventually become weakened and subject to failure. If the connection fails, the device may disengage from the vessel. Therefore, efforts continue to develop techniques that reduce the physician time required for such techniques, so that this time can be spent on other potentially life-saving measures.
U.S. Patent Publication No. 2009/0112237 to Paul, Jr. et al., which is incorporated herein by reference in its entirety, discloses examples of vascular conduits and delivery systems for open surgical placement. One such delivery system is depicted in FIG. 17A, which can include a tubular member, a dilator tip, a proximal handle, and a controller for manipulating the dilator tip. The delivery system may be configured to move the dilator tip axially relative to the tubular member between an extended position and a retracted position. At the retracted position, the dilator tip may be positioned around a distal portion of the vascular conduit, and at the extended position, the dilator tip can be positioned away from contact with the vascular conduit to permit deployment of the vascular conduit into the body vessel. Deployment of the vascular conduit into ends of a transected vessel using the delivery system is shown in FIGS. 23A-23E of the published application. As shown in FIGS. 23B and 23C, the dilator tip and portions of the vascular conduit disposed on the delivery system are positioned within the ends of the transected vessel. Once in the vessel, the dilator tip can be moved to the extended portion to permit anchoring of the vascular conduit to walls of the vessel.
Trauma physicians generally are familiar with using a stent delivery catheter and a splittable introducer sheath. Accordingly, when encountering patients having traumatic injury to a body vessel, it would be desirable for the trauma physician to deliver a medical prosthesis with a deployment system that operates similar to conventional stent delivery catheters and splittable sheaths to repair an injured body vessel. Thus, it would be desirable to provide a prosthesis deployment system for use in repair of an injured body vessel, such as an artery or a vein, (and in particular a transected vessel) during emergency open surgery in a manner that is time effective, that addresses the trauma at hand to the extent possible, and that utilizes techniques that may be readily practiced by an trauma physician.